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The surface characteristics of thermally and chemically modified wood, such as surface roughness, surface free energy (SFE) and wettability, are important properties that influence further manufacturing processes such as gluing and coating. The aim of this paper was to determine the influence of the surface roughness of thermally and chemically modified teak wood on their SFE, wettability and bonding quality for water-based acrylic and solvent-based alkyd varnishes. In addition, durability against subterranean termites in the field of these modified teak woods was also investigated to give a valuable information for their further application.

The woods tested in this study were fast-growing teak woods that were prepared in untreated and treated with furfuryl alcohol (FA), glycerol maleic anhydride (GMA) and thermal. SFE values were calculated using the Rabel method. The wettability values were measured based on the contact angle between varnish liquids and wood surfaces using the sessile drop method, and the Shi and Gardner model model was used to evaluate the wettability of the varnishes on the wood surface. The bonding quality of the varnishes was measured using a cross-cut test based on ASTM 3359-17 standard. In addition, durability against subterranean termites in the field of these modified teak woods was also investigated according to ASTM D 1758-06.

The results showed that furfurylated and GMA-thermal 220°C improved the durability of teak wood against termites. The furfurylated teak wood had the roughest surface with an arithmetic average roughness (Ra) value of 15.65 µm before aging and 27.11 µm after aging. The GMA-thermal 220°C treated teak wood was the smoothest surface with Ra value of 6.44 µm before aging and 13.75 µm after aging. Untreated teak wood had the highest SFE value of 46.90 and 57.37 mJ/m² before and after aging, respectively. The K values of untreated and treated teak wood increased owing to the aging treatment. The K values for the water-based acrylic varnish were lower than that of the solvent-based alkyd varnish. The untreated teak wood with the highest SFE produced the highest bonding quality (grades 4–5) for both acrylic and alkyd varnishes. The solvent-based alkyd varnish was more wettable and generated better bonding quality than the water-based acrylic varnish.

The originality of this research work is that it provides evaluation values of the durability and SFE. The SFE value can be used to quantitatively determine the wettability of paint liquids on the surface of wood and its varnish bonding quality.

The paper aims to understand Finnish architects' attitudes towards the use of timber as a structural material in multi-storey (over two--storeys high) residential construction.

The study was conducted through a literature survey mainly including international peer-reviewed journals and similar research projects. Furthermore, the literature survey informed the generation of the web-based survey questionnaire design to gather information on architects' perceptions, attitudes and interest in the use of wood in multi-storey (over two-storeys high) residential buildings.

The paper's findings are as follows: (1) respondents perceived the most important advantages of wood as a lightweight, local and ecological material; (2) wood construction (compared to concrete) included perceived concerns about it being more costly and needing more complex engineering and (3) respondents had a favourable overall attitude towards the use of wood particularly in low-rise residential construction, whilst their perception of tall housing, including timber ones, was mostly negative.

No studies have evaluated the use of wood in tall residential buildings and architects' perceptions in Finland.

This study describes a series of experiments investigating the upper hot layer temperature profile in a confined space under different ventilation conditions for porosity-controlled wood crib fires for pre-flashover conditions.

Full-scale compartment (4 m × 4 m × 4 m) experiments were carried out for four-door openings, i.e. 100%, 75%, 50% and 25% of the total vent area (2 m × 1 m) with the wood crib as a fuel load. The temperature of the upper hot smoke layers of the compartment was recorded with the help of four layers of thermocouples for varying vent areas.

The effect of ventilation on the properties, i.e. mass loss rate, enclosure temperature, heat release rate and carbon monoxide (CO) gas concentration, has been measured and analyzed. The effect of ventilation on heat flux and flame temperature has also been studied. Compartment gas temperature has been examined by five wood crib burning stages: Ignition, growth, steady burning, recess and collapse.

Findings demonstrate that the influence of vent openings varies for the burning parameters and upper layer temperature of the compartment. The current results are beneficial in analyzing thermal risks concerning compartment fire and fire safety engineering projects.

The purpose of this study is the development of sustainable and low-formaldehyde emission wood adhesive formulations.

Three-step urea formaldehyde (UF) resin has been in situ modified with calcium lignosulfonate (LS) and/or 1,4 butanediol diglycidyl ether (GE). The structural, chemical, thermal and morphological characterizations were carried out on resin samples. These resins have been applied for particleboard pressing, and UF, UF-LS and UF-GE were evaluated as P2 classes according to EN 312.

The results show that the improved LS- or diglycidyl ether-modified UF wood adhesives were successful in their adhesive capacity, and the formaldehyde content of the final product was obtained as low as 8 mg/100 g. This paper highlights that the presented adhesive formulations could be a potential eco-friendly and cost-effective alternative to formaldehyde-based wood adhesives for interior particleboard production.

Combination of LS and GE resulted in weaker mechanical properties and fulfilled P1 class particleboards due to temperature and duration conditions. Therefore, in situ usage of LS or GE in UF resins is highly recommended for particleboard pressing. Formaldehyde content of particleboards was determined with the perforator method according to EN 12460-5 and all of the particleboards exhibited E1 class. LS was more efficient in decreasing formaldehyde content than GE.

This study provides the application of particleboards with low formaldehyde emission.

The developed LS- and diglycidyl ether-modified UF resins made it possible to obtain boards with significantly low formaldehyde content compared with commercial resins.

The developed formaldehyde-based resin formulation made it possible to produce laboratory-scale board prototypes using LS or GE without sacrificing of press factors and panel quality.

A specific area of interest in the coaching literature is focused on exploring the intersection of personality and coaching; however, research has yet to explore whether coaching exerts reciprocal effects on personality traits (i.e. if personality trait change can accompany coaching). Utilizing the explanatory theoretical framing of the Demands-Affordances TrAnsactional framework (Woods et al., 2019), we propose that coaching may indirectly facilitate personality trait change by firstly enabling the coachee to reflect on their behaviors, second, implement desired behavioral changes which consequently facilitate personality trait change.

A quasi-experiment was conducted to explore coaching and personality trait change. Students participating in a demanding, work-based team simulation (N = 258), were assigned to either an intervention group (and received one-to-one coaching) or a control group (who received no intervention). Personality traits were measured before and after coaching and positioned as the dependent variable.

Results indicate that participants in the coaching group exhibited significant changes in self-reported agreeableness, conscientiousness, extraversion and core self-evaluations, which all significantly decreased after coaching; however, no change was observed for the control group.

We provide the first exploration of coaching and personality trait change, contributing to both the coaching literature, by providing evidence regarding the efficacy of coaching to facilitate personality trait change in coachees, and the personality literature, by highlighting coaching as an important tool for those interested in personality trait change. Our research also has implications for other interventions such as mentoring, as we provide support for the notion that interventions can support personality trait change.

There is a strong consensus among scholars that the international competitiveness of companies strongly depends on the support of institutions, which reduces uncertainty in transactions by giving form to economic interactions, while less attention was paid to the role of international standards within this context. This study intends to propose its contribution by deepening the role of process certifications in the competitiveness and internationalization strategies of companies, with specific reference to the wood-furniture sector.

Data were collected using a questionnaire survey distributed via computer-assisted web interviewing (CAWI) methodology and sent to a sample of 2,845 Italian companies which operate in the wood-furniture industry, using simple random sampling. Thanks to the survey administration, 228 companies participated to the survey.

The study shows that it is companies operating in international markets that define this tool as relevant; this underlines how certification is seen as a kind of business card for entering international markets. In this context, the role of business leadership emerges as fundamental in the practical definition of the objectives to be set by adopting a quality management systems and in the subsequent commitment to obtain them.

Up to now, the literature has taken these elements into analysis mainly considering the consumers' perspective. In sectors with a higher content of innovation, technology and design, such as the wood-furniture sector, the literature appears to be poor in terms of contributions.

The use of energy efficient cookstoves (EECS) has been promoted for a long and considered as instrumental in the efforts to mitigate the multiple social, economic and environmental consequences of traditional biomass cookstoves. Despite this, the adoption of EECS in pre-urban and rural Ethiopia is still very low. In response to this, the government of Ethiopia, in collaboration with international development organizations, implemented numerous initiatives aimed at improving the availability and use of EECS as part of the effort to support sustainable development. However, very little is known about the impact of the introduced EECS on improving the welfare of women. The purpose of this study is, therefore, to assess the impact of improved cookstoves projects on the welfare of women in Yaya Gullele district, Ethiopia.

A mixed research design was adopted to conduct the study. The quantitative data for the study were collected using a structured questionnaire by interviewing 388 randomly selected respondents. The data were analysed using both descriptive and inferential data analysis techniques, including the propensity score matching model using STATA.

Results of the study revealed that adoption of EECS has reduced fuel wood expense (124.65 Ethiopian Birr [ETB]/week), reduced five-year stove expense (404.67 ETB) and increased regular savings (116.58 ETB/month), which contributed for an increased annual income of participants (5,594.42 ETB). The result of the study also indicated that the use of EECS enabled the beneficiary women to reduce the amount of fuel wood use by 29.4 kg/week, which in turn reduced forest degradation and emission by 2.34 tons of CO₂e/year/household. Besides, it reduced the drudgery on women in terms of reduced time to cook (53 min/day), reduced time to collect fuelwood and prepare food (3.95 h/week) and reduced frequency of fuelwood collection trips (3.42 trips/week). The study results, in general, indicated that the adoption of EECS improved the welfare of women in the study area, where the majority of women have been suffering from the burden of using traditional stoves and associated impacts for a long.

Energy is central to most of the development-related challenges and opportunities every country faces today. The result of the study implied that policies and strategies intended at improving the availability and use of EECS as part of the effort to support sustainable development need to consider integrating such context-referenced, locally manageable and affordable EECS into the clean developmental strategies of the country.

Insights from this study can support development practitioners and policymakers to make informed decisions regarding future interventions in the use of energy efficient that have the potential to several economic, social and environmental positive development outcomes.

The number of people with special needs, including citizens and military personnel, has increased as a result of terrorist attacks and challenging conditions in Iraq and other countries. With almost 80% of the world’s amputees having below-the-knee amputations, Iraq has become a global leader in the population of amputees. Important components found in lower limb prostheses include the socket, pylon (shank), prosthetic foot and connections.

There are two types of prosthetic feet: articulated and nonarticulated. The solid ankle cushion heel foot is the nonarticulated foot that is most frequently used. The goal of this study is to use a composite filament to create a revolutionary prosthetic foot that will last longer, have better dorsiflexion and be more stable and comfortable for the user. The current study, in addition to pure polylactic acid (PLA) filament, 3D prints test items using a variety of composite filaments, such as PLA/wood, PLA/carbon fiber and PLA/marble, to accomplish this goal. The experimental step entails mechanical testing of the samples, which includes tensile testing and hardness evaluation, and material characterization by scanning electron microscopy-energy dispersive spectrometer analysis. The study also presents a novel design for the nonarticulated foot that was produced with SOLIDWORKS and put through ANSYS analysis. Three types of feet are produced using PLA, PLA/marble and carbon-covered PLA/marble materials. Furthermore, the manufactured prosthetic foot undergoes testing for dorsiflexion and fatigue.

The findings reveal that the newly designed prosthetic foot using carbon fiber-covered PLA/marble material surpasses the PLA and PLA/marble foot in terms of performance, cost-effectiveness and weight.

To the best of the author’s knowledge, this is the first study to use composite filaments not previously used, such as PLA/wood, PLA/carbon fiber and PLA/marble, to design and produce a new prosthetic foot with a longer lifespan, improved dorsiflexion, greater stability and enhanced comfort for the patient. Beside the experimental work, a numerical technique specifically the finite element method, is used to assess the mechanical behavior of the newly designed foot structure.

The purpose of this review paper is to provide a review of the most recent advances in the field of manufacturing composite sandwich panels along with their advantages and limitations. The other purpose of this paper is to familiarize the researchers with the available developments in manufacturing sandwich structures.

The most recent research articles in the field of manufacturing various composite sandwich structures were reviewed. The review process started by categorizing the available sandwich manufacturing techniques into nine main categories according to the method of production and the equipment used. The review is followed by outlining some automatic production concepts toward composite sandwich automated manufacturing. A brief summary of the sandwich manufacturing techniques is given at the end of this article, with recommendations for future work.

It has been found that several composite sandwich manufacturing techniques were proposed in the literature. The diversity of the manufacturing techniques arises from the variety of the materials as well as the configurations of the final product. Additive manufacturing techniques represent the most recent trend in composite sandwich manufacturing.

This work is valuable for all researchers in the field of composite sandwich structures to keep up with the most recent advancements in this field. Furthermore, this review paper can be considered as a guideline for researchers who are intended to perform further research on composite sandwich structures.

This study aims to prepare a low-formaldehyde and environmentally friendly glucose-lignin-based phenolic resin.

The authors directly used lignin to substitute formaldehyde to prepare lignin-based phenolic resin (LPF) with urea as formaldehyde absorbent. To improve the performance of the adhesive, the biobased glucose was introduced and the modified glucose-LPF (GLPF) was obtained.

The results showed that when the replacing amount of lignin to formaldehyde reached 15 Wt.%, the physical properties of the prepared LPF met the Chinese national standard, and the bonding strength increased by 21.9%, from 0.75 to 0.96 MPa, compared with PF. The addition of glucose boost the performance of wood adhesive, for example, the free phenol content of the obtained GLPF was significantly reduced by 79.11%, from 5.60% to 1.17%, the bonding strength (1.19 MPa) of GLPF increased by 19.3% in comparison to LPF and the curing temperature of GLPF decreased by 13.08%.

The low-formaldehyde and environmentally friendly GLPF has higher bonding strength and lower curing temperature, which is profitable to industrial application.

The prepared GLPF has lower free formaldehyde and formaldehyde emission, which is cost-effective and beneficial to human health.

The joint work of lignin and glucose provides the wood adhesive with increased bonding strength, decreased free phenol content and reduced curing temperature.